One piece belly owner produced part?

[jetdriven]

With a big enough press, an aluminum version could be formed easily enough, but would still need some additional internal structure to make it viable where as the carbon fiber or fiberglass versions might not.  Of course the tooling costs for a 1-pc aluminum would be too high to justify, and few of us have access to a press either.  I bet one could be designed, however, and built from smaller pieces of aluminum and assembled into a big piece that replicates the easy access of the later model designs.

 

I've never read any claims that the factory 1-pc belly improves anything aerodynamically...just makes for easier maintenance.

 

 

If you add all the 40 hours of labor to install a fiberglass belly panel, you can pull those aluminum panels off and reinstall 20 times, which is good for 20 annuals-worth of labor on those panels.

 

I never saw a shop which knocked two hours off the flat rate for annuals of planes with the one-piece belly.

 

And further, you still lose the 30 lbs of useful load, which seems to be OK for belly panels but a cardinal sin if it involves installing bladders

[KSMooniac]

If you add all the 40 hours of labor to install a fiberglass belly panel, you can pull those aluminum panels off and reinstall 20 times, which is good for 20 annuals-worth of labor on those panels.

 

I never saw a shop which knocked two hours off the flat rate for annuals of planes with the one-piece belly.

 

And further, you still lose the 30 lbs of useful load, which seems to be OK for belly panels but a cardinal sin if it involves installing bladders

 

Guess you don't have to ask why I still have multiple belly panels and hundreds of screws.  

 

(and >1000 lbs of useful load)

 

FTR, I believe Wheat's carbon fiber panel STC is weight-neutral.  

[jetdriven]

Its only around a hundred screws. After working on my machine so much, I can have the panels off and on in one hour.

[Alan Fox]

The one piece belly is not a speed mod , it is a faster easier repair for when you gear it up......the one piece belly has about 60 screws anyway......About 5 minutes difference when you use a screw gun.........Spend your money on something that actually benefits you....

[scottfromiowa]

The one piece belly is not a speed mod , it is a faster easier repair for when you gear it up......the one piece belly has about 60 screws anyway......About 5 minutes difference when you use a screw gun.........Spend your money on something that actually benefits you....

That's funny.

[scottfromiowa]

Viagra?

[jetdriven]

Viagra?

:lol:

[fantom]

Usually when I do it, though, I spend more time inspecting and cleaning than I do actually screwing......

TMI

I have seen several big shops quote $100 less for a one piece belly panel annual. Don't recall who, but it sure wasn't DMax.

[drbob]

isaacpr7:

   pm me re: composite (short) belly fairing

                                                                    TIA  drbob

[pinerunner]

I watching the Mike Busch's video on owner produced parts and this is what I got from it:

 

Owners may produce parts on certified aircraft, so long as they are involved in the design and production process. They may not produce a part for sale to other aircraft. This is the video below. Maybe someone can watch it and help me interpret what I thought was right or wrong:

 

http://www.eaavideo.org/video.aspx?v=1105297993001

I watched this vid too and came away thinking there was a bit more wiggle room than I had previously believed. But the rule isn't often used by small aircraft owners and you'd better be ready for arguments about it if you use it. And then comes the part where you try to sell it and the buyer's eyebrows go up. What I recall? It's different from exact reproduction of existing parts which rebuilding mechanics do all the time (my dad used to reproduce belly skins having only simple curves in his rebuild projects). There must be some owner involvement in the process even if just a token scribble on a drawing. it will be a one-time custom part for that airplane. Busch's vid says that its common on large carriers who have engineers on staff and make often make subtle mods; nothing structural.  Maybe it allows some of these extra steps and tying points that you see on some bush planes. Maybe on a vintage plane that's got one stupid un-buyable broken bracket it gives you a way to not be grounded. Interesting point this vid. 

[aviatoreb]

Does anyone have a link to the carbon fiber smooth belly that someone has reported was a recent STC?  Any idea of cost and time and so forth?

[KSMooniac]

Call Dugosh/Gemini and see if they have the info.  Bill Wheat developed it with Dugosh, or just used them as a sales outlet IIRC.  Cost was ~ 4 AMU I believe, plus installation.  

[Marauder]

Does anyone have a link to the carbon fiber smooth belly that someone has reported was a recent STC? Any idea of cost and time and so forth?

Let us know what you find out. Always wanted a single piece belly.

[aviatoreb]

Let us know what you find out. Always wanted a single piece belly.

 

I'm not calling at this time....not serious enough yet/  I am thinking of a paint job at some point and maybe I would do this before - maybe.

 

I did do a google search and no sign of this stc that I could find.

[piperpainter]

The one piece belly is awesome. I have it and I wouldn't give it away for the....okay maybe for an F model! Anyway, I used to have my mechanic come to me and ask me to take my belly off real quick to find the exact location of something on another Mooney! It takes me all of about 2 minutes total to take it off. And while it's off and stand up against the wall I can easily spray some cleaner on it and whip it down. It's rough!  

[M20F-1968]

The conversion to a one piece belly pan is not trivial.  Much of the structure supporting the original panels are removed and new structure substituted.  It takes quite a bit of time.  However, that structure is all approved data.  There are compound curves on the belly pan which would make it difficult to fabricate it from aluminum sheet, unless it were stamped (you would not want to pay for the die) or formed by riveting small sheets into a compound curved one piece panel (which defeats the purpose).  Composites are the way to go and fiber is lighter but hared to work with.

 

John Breda